In addition to being crucial for healthy sexual development, the thyroid is also extremely important for healthy growth. Thyroid hormones play a key role in producing the bone material necessary for a growing body, and thus an under active thyroid often leads to slow growth.If a child is born with an under active thyroid, they will usually experience stunted bone growth resulting in a loss in height, while if a child acquires hypothyroidism after birth it will usually result in stunted height growth combined with weight gain. Thus, a child with acquired hypothyroidism will often be shorter than average for their age and heavier than average for their age.Next